Statistical Clustering of Major Solutes: Use as a Tracer for Evaluating Interbasin Groundwater Flow into Indian Wells Valley, California

Geological Society of America (GSA) | February 9th, 2006

Many previous studies have demonstrated use of specific solutes or isotopes as tracers of groundwater flow. We present a technique that uses standard hydrochemical inform

Many previous studies have demonstrated use of specific solutes or isotopes as tracers of groundwater flow. We present a technique that uses standard hydrochemical information to create statistically based hydrochemical facies, which are then used as tracers of groundwater flow. This approach reduces potential subjective bias during interpretation of single tracer data in complex systems with multiple sources or conflicting multiple tracer data. Standard hydrochemical data from 1,368 water samples that spanned more than 80 years were analyzed using cluster analysis to decipher groundwater flow paths in Indian Wells Valley (IWV), California. The statistically derived hydrochemical facies form distinct spatial patterns in which all major-ion concentrations increase progressively from Sierra Nevada (recharge) to China Lake playa (discharge), consistent with the topographically driven flow of groundwater (the typical case for basin and range flow systems). However, once individual samples could be placed in the context of the normal hydrochemical evolution, anomalies are readily identifiable. The distribution of water chemistry in the southeastern part of the IWV does not conform to the regional trend. Groundwater from that part of the IWV is statistically more similar to waters from the Kern Plateau area (in the high Sierra Nevada outside the local watershed) than to waters from the local watershed. The groundwater is interpreted to originate from the fracture-directed interbasin flow from the Kern Plateau area that is directly recharging the alluvial aquifer in the subsurface. Inclusion of this flow could substantially alter current water budgets and water resources management approaches.

The Importance of Interflow to Groundwater Recharge in a Snowmelt-Dominated Headwater Basin

American Geophysical Union (AGU) | May 23rd, 2019

Understanding the sensitivity of groundwater generation to climate in a mountain system is complicated by the tight coupling of snow dynamics to vegetation and topogr

Understanding the sensitivity of groundwater generation to climate in a mountain system is complicated by the tight coupling of snow dynamics to vegetation and topography. To address these feedbacks, we combine LiDAR-derived snow observations with an integrated hydrologic model to quantify spatially and temporally distributed water fluxes across varying climate conditions in a Colorado River headwater basin. Results indicate annual groundwater flow is an important and stable source of stream water. However, interflow decreases during drought as a function increased plant water use and the relative fraction of groundwater to streams increases. Seasonal snowmelt and vegetation water use regulate small recharge rates in the lower portions of the basin, but snowmelt transported via interflow from high mountain ridges toward convergent topographic zones define preferential recharge in the upper subalpine. Recharge in this zone appears decoupled from annual climate variability and resilient to drought. 

The relative contributions of summer and cool-season precipitation to groundwater recharge, Spring Mountains, Nevada, USA

Hydrogeology Journal (Springer) | June 1st, 1998

A comparison of the stable-isotope signatures of spring waters, snow, snowmelt, summer (July thru September) rain, and cool season (October thru June) rain indicates that

A comparison of the stable-isotope signatures of spring waters, snow, snowmelt, summer (July thru September) rain, and cool season (October thru June) rain indicates that the high-intensity, short-duration summer convective storms, which contribute approximately a third of the annual precipitation to the Spring Mountains, provide only a small fraction (perhaps 10%) of the recharge to this major upland in southern Nevada, USA. Late spring snowmelt is the principal means of recharging the fractured Paleozoic-age carbonate rocks comprising the central and highest portion of the Spring Mountains. Daily discharge measurements at Peak Spring Canyon Creek during the period 1978–94 show that snowpacks were greatly enhanced during El Niño events.

Three-dimensional geologic mapping of the Cenozoic basin fill, Amargosa Desert basin, Nevada and California

U.S. Geological Survey (USGS) | July 1st, 2014

Understanding the subsurface geologic framework of the Cenozoic basin fill that underlies the Amargosa Desert in southern Nevada and southeastern California has been impr

Understanding the subsurface geologic framework of the Cenozoic basin fill that underlies the Amargosa Desert in southern Nevada and southeastern California has been improved by using borehole data to construct three-dimensional lithologic and interpreted facies models. Lithologic data from 210 boreholes from a 20-kilometer (km) by 90-km area were reduced to a limited suite of descriptors based on geologic knowledge of the basin and distributed in three-dimensional space using interpolation methods. The resulting lithologic model of the Amargosa Desert basin portrays a complex system of interfingered coarse- to fine-grained alluvium, playa and palustrine deposits, eolian sands, and interbedded volcanic units. Lithologic units could not be represented in the model as a stacked stratigraphic sequence due to the complex interfingering of lithologic units and the absence of available time-stratigraphic markers. Instead, lithologic units were grouped into interpreted genetic classes, such as playa or alluvial fan, to create a three-dimensional model of the interpreted facies data. Three-dimensional facies models computed from these data portray the alluvial infilling of a tectonically formed basin with intermittent internal drainage and localized regional groundwater discharge. The lithologic and interpreted facies models compare favorably to resistivity, aeromagnetic, and geologic map data, lending confidence to the interpretation.

Two-dimensional, steady-state model of ground-water flow, Nevada Test Site and vicinity, Nevada- California: U.S. Geological Survey Water-Resources Investigations Report 82-4085

U.S. Geological Survey (USGS) | July 1st, 1962

Upper San Gabriel Valley Municipal Water District v. City of Alhambra et al

Superior Court of California, County of Los Angeles | June 21st, 2012

Background note from An Evaluation of California’s Adjudicated Groundwater Basins by Langridge et al, (UC Davis) 2016 The Main San Gabriel Basin is one of the larges

Background note from An Evaluation of California’s Adjudicated Groundwater Basins by Langridge et al, (UC Davis) 2016 The Main San Gabriel Basin is one of the largest groundwater basins in southern California, providing residents of the greater San Gabriel Valley with about 240,000 AF per year. It is geographically situated in the south-easterly portion of Los Angeles County and bounded on the north by the San Gabriel Mountains, on the northwest by Raymond Basin, on the southeast by Puente Basin, and on the south by the Central Basin. The adjudication of the basin was deemed necessary by water producers to streamline administration, reduce overdraft, and adhere to the Long Beach Judgment and Puente Narrows Agreements, and the adjudication was relatively amenable. One of the most significant concerns in the basin is water quality, with four areas of the valley containing Superfund sites. The 1973 Judgment included water quality as one of the Watermaster’s responsibilities, and since the mid-1980s the Watermaster has coordinated with regulatory agencies to have groundwater remediation facilities constructed, permitted and operated to protect and enhance the groundwater supplies. The 1992 Judgment amendment explicitly required coordination with EPA for a federal cleanup of the Superfund sites.